The present invention relates to an information recording medium which has a plurality of sector fields that record data, and in which a block is defined by a set of a predetermined number of sector fields, for example, a DVD (Digital Versatile Disk). The present invention also relates to an information recording apparatus and method for recording information on the information recording medium. Furthermore, the present invention relates to an information reproduction apparatus and method for reproducing information from the information recording medium.
In recent years, information recording media such as a DVD that features high-density recording have been extensively studied and developed. Such information recording medium has a plurality of sector fields which record data, and an ECC (Error Correction Code) block is defined by a set of a predetermined number of sector fields.
Even when data is recorded on some sector fields of such information recording medium, the entire ECC block which includes target sector fields as a recording destination is read. Of the read ECC block data, target data patches a portion corresponding to the target sector fields, and the ECC block is re-arranged and recorded in the original ECC block. Such recording in units of sector fields is called read-modify-write.
Such read-modify-write is suitable for recording PC data that does not require real-time processes but is not suitable for recording AV data that places an importance on real-time processes since it is relatively time-consuming. In order to avoid read-modify-write, data can be recorded in units of ECC blocks.
Upon recording AV data, in general, initial defect management that registers initial defects by format and certify is not made. That is, defects remain on the recording space. Upon recording AV data, it is important to continue recording without any interruption ignoring some errors (defects) in sector fields as a recording destination.
However, when both PC and AV data are recorded on a single information recording medium, especially, when PC data is overwritten on AV data, the error rate increases upon read-modify-write due to the absence of defect management. That is, ECC block data cannot be read out upon read-modify-write, that ECC block consequently cannot undergo a replacement process, and read-modify-write terminates abnormally.